Merge branch 'sverker/trace_gc-bug/OTP-14154' into maint

* sverker/trace_gc-bug:
  erts: Fix GC tracing to use temp heap
  erts: Assert sufficient space need after GC

3 files changed, 9 insertions, 4 deletions

diff --git a/erts/emulator/beam/erl_gc.c b/erts/emulator/beam/erl_gc.c
index 669f2bc610..edbdbb4b8f 100644
--- a/erts/emulator/beam/erl_gc.c
+++ b/erts/emulator/beam/erl_gc.c
@@ -616,7 +616,7 @@ garbage_collect(Process* p, ErlHeapFragment *live_hf_end,
     Uint reclaimed_now = 0;
     Eterm gc_trace_end_tag;
     int reds;
-    ErtsMonotonicTime start_time = 0; /* Shut up faulty warning... */
+    ErtsMonotonicTime start_time;
     ErtsSchedulerData *esdp;
     erts_aint32_t state;
     ERTS_MSACC_PUSH_STATE_M();
@@ -624,6 +624,7 @@ garbage_collect(Process* p, ErlHeapFragment *live_hf_end,
     DTRACE_CHARBUF(pidbuf, DTRACE_TERM_BUF_SIZE);
 #endif
 
+    ERTS_UNDEF(start_time, 0);
     ERTS_CHK_MBUF_SZ(p);
 
     ASSERT(CONTEXT_REDS - ERTS_REDS_LEFT(p, fcalls)
@@ -790,6 +791,7 @@ do_major_collection:
 
     ASSERT(!p->mbuf);
     ASSERT(!ERTS_IS_GC_DESIRED(p));
+    ASSERT(need <= HEAP_LIMIT(p) - HEAP_TOP(p));
 
     return reds;
 }
diff --git a/erts/emulator/beam/erl_nif.c b/erts/emulator/beam/erl_nif.c
index 6b265a8b80..19ce0f6965 100644
--- a/erts/emulator/beam/erl_nif.c
+++ b/erts/emulator/beam/erl_nif.c
@@ -3561,8 +3561,8 @@ Eterm erts_nif_call_function(Process *p, Process *tracee,
 #endif
     if (p) {
         /* This is almost a normal nif call like in beam_emu,
-           except that any heap fragment created in the nif will be
-           discarded without checking if anything in it is live.
+           except that any heap consumed by the nif will be
+           released without checking if anything in it is live.
            This is because we cannot do a GC here as we don't know
            the number of live registers that have to be preserved.
            This means that any heap part of the returned term may
diff --git a/erts/emulator/beam/erl_trace.c b/erts/emulator/beam/erl_trace.c
index 8c84303997..ac9e91e31f 100644
--- a/erts/emulator/beam/erl_trace.c
+++ b/erts/emulator/beam/erl_trace.c
@@ -1436,6 +1436,7 @@ void
 trace_gc(Process *p, Eterm what, Uint size, Eterm msg)
 {
     ErtsTracerNif *tnif = NULL;
+    Eterm* o_hp = NULL;
     Eterm* hp;
     Uint sz = 0;
     Eterm tup;
@@ -1446,7 +1447,7 @@ trace_gc(Process *p, Eterm what, Uint size, Eterm msg)
         if (is_non_value(msg)) {
 
             (void) erts_process_gc_info(p, &sz, NULL, 0, 0);
-            hp = HAlloc(p, sz + 3 + 2);
+            o_hp = hp = erts_alloc(ERTS_ALC_T_TMP, (sz + 3 + 2) * sizeof(Eterm));
 
             msg = erts_process_gc_info(p, NULL, &hp, 0, 0);
             tup = TUPLE2(hp, am_wordsize, make_small(size)); hp += 3;
@@ -1455,6 +1456,8 @@ trace_gc(Process *p, Eterm what, Uint size, Eterm msg)
 
         send_to_tracer_nif(p, &p->common, p->common.id, tnif, TRACE_FUN_T_GC,
                            what, msg, THE_NON_VALUE, am_true);
+        if (o_hp)
+            erts_free(ERTS_ALC_T_TMP, o_hp);
     }
 }